In a time division duplexing TDD (Time Division Duplexing) wireless communication system of a long term evolution LTE (Long Term Evolution)/an enhanced long term evolution LTE-A (LTE Advanced), each radio frame includes 10 subframes, and the subframe can be a downlink subframe, an uplink subframe or a special subframe depending on service usage of the subframe. Among them, the special subframe consists of three special time slots, i.e., a downlink pilot time slot DwPTS (Downlink Pilot Time Slot), a guard period GP (Guard Period), and an uplink pilot time slot UpPTS (Uplink Pilot Time Slot).
The DwPTS of a frame structure in an LTE TDD system can be configured with 3 to 12 orthogonal frequency division multiplexing (OFDM) (Orthogonal Frequency Division Multiplexing) symbols in length, used for downlink transmission. The UpPTS can be configured with 1 to 2 OFDM symbols in length, used for uplink transmission. The GP is a guard interval between the uplink transmission and the downlink transmission, mainly consisting of a “round-trip time RTT (Round-trip Time)” and a “device transceiver conversion time delay”. The device transceiver conversion time delay generally does not exceed a length of one OFDM symbol, and an RTT corresponding to a coverage radius of a cell mainly affects a GP length.
In the prior art, the GP length should be greater than or equal to a sum of a maximum RTT of the cell and the device transceiver conversion time delay, so that normal handover between downlink and uplink signals can be performed by a user at the edge of the cell. The GP resources occupy a lot of system resources, and a cell with a larger radius needs to configure with a larger GP. A user equipment (UE, User Equipment) close to a base station, upon receiving downlink data of the base station, sends uplink data only after waiting for a period of time in vain due to a small RTT thereof, and therefore, the system resources cannot be effectively utilized.